Chapter 7 - The Axial Skeleton Flashcards
Axial Skeleton
80 bones on longitudinal axis
Appendicular Skeleton
126 bones of upper and lower limbs and girdles.
Long bone
Shaft and variable number of extremities or epiphyses, slightly curbed for strength. Mostly compact bonne tissue, but some spongy in ends. Femur, tibia, fibula, humerus, ulna, radius, phalanges.
Short bone
Somewhat cube shaped, spongy except compact surface. Wrist, ankle.
Flat bone
Thin, plate of compact over plate of spongy, cranial bones, sternum, ribs, scapulae.
Irregular bone
Vary, vertebrae, hips, some face, calcaneus.
Sesamoid bone
tendons with friction (palms and soles), pattellae, quadriceps femoris tendon. Protect tendons.
Sutural bone
Small bones located in sutures between some cranial bones.
Frontal bone
Forehead
Supraorbital margin, foramina, notch, frontal sinuses
Superior border of the orbits, the frontal bone thickens.
Foramina = hole (brow pressure point)
incomplete hole = notch
Parietal bones
Sides and roof of cranial cavity.
Temporal bones
Inferior lateral aspect of the cranium and part of the cranial floor.
Temporal squama = temple
Zygomatic, mastoid, styloid processes
Z=cheek, M=attachment point for neck muscle
S=attachment for ligaments of tongue and neck
Madibular fosa
Socket on the inferior posterior surface of the zygomatic process of each temporal bone
Zygomatic arch
zygomatic process of the temporal bone and the temporal process of the zygomatic bone.
External auditory meatus
Ear canal, detects sound waves
Internal auditory meatus
opening through facial 7 nerve and vestibulocochlear 8 nerve
Occipital bone
Posterior part and most of the base of cranium
Foramen magnum
Inferior large hole, medulla oblongata connects with spinal cord through this hole
Occipital condyles
articulate with depressions on c1 for”yes” oval processes with convex surface on either side of the foramen magnum.
External occipital protuberance
Prominent midline projection on the posterior surface of the bone (bump above neck)
Sphenoid bone
keystone of cranial floor, butterfly.
Sella turcica
Bony saddle-shaped structure on the superior surface of the body of the sphenoid.
Optic foramen
Through which the optic 2 nerve and ophthalmic artery pass into orbit
Ethmoid bone
spongelike appearance. (1) part of the anterior portion of the cranial floor; (2) the medial wall of the orbits; (3) the superior portion of the nasal septum, a partition that divides the nasal cavity into right and left sides; and (4) most of the superior sidewalls of the nasal cavity. The ethmoid bone is a major superior supporting structure of the nasal cavity and forms an extensive surface area in the nasal cavity.
Superior and middle nasal conchae
scroll-shaped projections lateral to the nasal septum. The conchae greatly increase the vascular and mucous membrane surface area in the nasal cavity, which warms and moistens (humidifies) inhaled air before it passes into the lungs. The conchae also cause inhaled air to swirl; as a result, many inhaled particles become trapped in the mucus that lines the nasal cavity. Increase surface area for smell.
Nasal bones
Small, flat, rectangular bones that form the bridge of the nose.
Lacrimal bones
(look like a fingernail) Posterior and lateral to nasal bones, form medial wall.
Lacrimal fossa
a vertical tunnel formed with the maxilla, that houses the lacrimal sac, a structure that gathers tears and passes them into the nasal cavity
Palatine bones
L-Shaped, posterior portion of the hard palate, part of the floor and lateral wall of the nasal cavity, small portions of the floors of the orbits.
Inferior nasal conchae or turbinates
Scroll-like bones form part of the inferior lateral wall of the nasal conchae, increase SA of air but dont smell.
Vomer
Triangular bone on the floor of nasal cavity. Forms inferior portion of the bony nasal septum, the partition that divides the nasal cavity
Maxillae & Hard Palate
Upper jawbone.
Hard Palate is the roof of mouth.
Maxillary sinus
Empties into nasal cavity
Infraorbital foramen
Opening in the maxilla inferior to the orbit, allows passage of the infraorbital blood vessels and nerve
Zygomatic bones
Cheekbones.
Mandible
Lower jawbone. strongest and only movable in skull.
Mandible - Body
Curved horizontal portion
Mandible - Rami
Two perpendicular portions
Mandible -Angle
where each ramus meets body